1. Field of the Invention
The present invention relates in general to a semiconductor device and a method of manufacturing the same. More particularly, it relates to such a device composed of a polycrystalline semiconductor and a method of manufacturing the same.
2. Description of the Prior Art
Solar cells made of polycrystalline semiconductors have been manufactured by depositing a laminate composed of a lower conductive film, a photoconductive semiconductor film and an upper conductive film on glass substrates. The semiconductor film is deposited first in the form of an amorphous semiconductor film such as an a-Si film followed by thermal crystallization, for example at 600.degree. C., in order to change the amorphous film to a polycrystalline film.
The thermal treatment for recrystallization has to be continued for several tens of hours. The amorphous semiconductor films often crack or come off from the substrates due to thermal contraction thereof. The cracks tend to form short current paths through the semiconductor film. In the case of a solar cell having a PIN junction for example, the p-type layer and the i-type layer are easily shorted through such cracks so that the electric characteristics are seriously deteriorated.